But the process used to make BHO can lead to explosions so violent they can flatten surrounding buildings.

The Green Team squad of the Alberta Law Enforcement Response Teams or ALERT focuses on busting grow-ops.

Sgt. Dwayne Karpo said officers are seeing more evidence of BHO production.

“Probably one out of every five grows that we’re going to, some sort of conversion lab is what we’re seeing,” he said. “Whereas before, you may see one out of every ten.”

Last year, an explosion near Evansburg killed one man and sent another to hospital with serious injuries.

Karpo believes it’s only a matter of time before something happens in Edmonton.

Legalization hasn't stopped lab explosions

Advocates believe the problem can be solved by legalizing marijuana which would allow hash oil to be produced in safe, government-sanctioned facilities.

But Karpo disagrees. The state of Colorado legalized marijuana at the beginning of 2014. Since then, there have been 26 confirmed hash oil fires compared to only 12 in all of 2013.

“Colorado has actually gotten worse. It’s exploded down there,” he said. “They legalized their marijuana, now people are getting into the market. There’s a demand for it. So why wouldn’t you make it.”

Some say illegal production continues because there have been problems with legal facilities keeping up with demand.

Craig Jones with the National Organization to Reform Marijuana Laws in Canada (NORML) says it’s still too early in Colorado to judge the effects of legalization.

“I’m anticipating that eventually the market will stabilize,” he said. “There will always be problem users but the vast majority of cannabis users will not be problem users which is the same for alcohol.”

Police are trying to decrease demand for hash oil as well as spreading the word about the dangers of home labs.

Hash oil can be consumed without detection using e-cigarettes. After police pointed this out, the public and Catholic school boards in Edmonton banned e-cigarettes from school property.

Police are also trying to crack down on labs. They want the public to call them if anyone sees a lot of butane canisters in a neighbour’s garbage.